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Spent some time reading this thread and love this idea. Can’t believe more people don’t want the bump in low end power. That’s honestly all I’m looking. For also out of this car. It’s fun over 6k but needs something to get it up to that point.
I went big turbo on my rs and ya it’s fast but lost something special giving you all that low end.
I've sort of done this to my 4 port 6 speed manual with a 0.86 a/r GTX3076. Let me tell you it drives like a turbocharged diesel in the low end with the top end of a 6 port renesis on low boost at redline.
Does 300whp, but on "high" boost at 15 psi. Keep in mind the intake and exhaust ports of the 4 port are even smaller than the 6 port, so it does require a lot of boost to make even 300g/s.
Do I love it? Of course! Very zippy town car with plenty of grunt to overtake on single carriageway roads.
Primary intake ports are 5° smaller(close sooner) so are exhaust ports(open later). The secondary ports are 5° bigger, but the aux ports don't exist. This shows a lot on the boost vs airflow, I'm not getting even 250g/s on 6 psi, which a 6 port would do.
Because again; it has 6 intake ports and your engine only has 4 intake ports. The other stuff you’re talking about is minor.
Let’s also be clear that you don’t have a GT3076. What you have a cheap piece of kluged metal bits from china that claims to be something they are often well known not to be. I get that it was a cheap build and you don’t want to invest a lot into it, but then your results aren’t necessarily going to accurately represent the situation either.
In addition to not having those extra two intake ports, it could just as much be the turbo giving what was paid for. Or there could be any number of other issues from the intake filter to exhaust tip with all of the undersized piping and other minimum cost bits you used.
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None of what you said is true though. My intake is 3", my charge pipes are 2,5" and the exhaust is 3"->2,5".
SInce the last time I posted about it I've put an original bb garret turbo on the car, the chinese crap is gone. That turbo had a 0.64 a/r and could not flow anything past 200g/s. I know what you're refferencing but its simply not the case anymore. But feel free to point me towards another 4 port turbo build with psi vs airflow vs hp to compare.
You need an extra 3-4 psi up top from a 4 port to make the same power as a 6 port (even then you miss out on 1000 rpm of useable power band), that has been well established over the years.
Not a worry if you are running an ethanol blend making it safe , but on pump gas the 6 port can make 35-45 more whp without any need to upgrade fuel.
so I’m unlikely to ever build a 4-Port Renesis now, but just updating that I found a supplier for an EFR7163 twin scroll EWG turbine housing of substantial A/R that should improve peak flow quite a bit. This with the SX-E compressor cover will essentially convert an EFR7163 into the equivalent of an EFR7670 hybrid in a B1 frame configuration. So I’m still pursuing still using this turbo as a future Renesis 6-port project.
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Picture posted below they sent me of the EFR7163 fitted to a much larger A/R EWG turbine housing with the original 0.80 A/R IWG housing next to it. It may arrive here tomorrow or Saturday maybe, but maybe not because of the ice storm that blew in last night delaying things.
Had to suffice with a divided T3 1.25 A/R rather than a T4. It’s not as ideal for the manifold design compared to a divided T4, but ultimately the limitation is the 63mm inducer/56mm exducer turbine wheel in this flow level range. It should still allow the turbo to pass enough flow to put it in the EFR7670 turbine housing range, yet in a smaller overall package.
Also plan to ditch the EFR compressor cover for the more efficient and higher flowing SX-E cover to try and squeeze all the blood out of this onion. Considering sending the turbine housing to be extrude honed for the same reason, but am a bit unsure about this. Have seen and heard of other people doing this, but never any results that qualify if it actually achieving better performance.
also pretty interesting how much difference the SX-E compressor cover made over the EFR cover on this 4-banger application, I suspect the larger inlet was just as much helping as the larger A/R
66 ft-lbs and 63 whp increase with a very slight loss below ~4200 rpm
ordered the SX-E cover from Hayward, CA on Saturday afternoon with standard shipping from the only place that seems to have then in stock and somehow received it Monday afternoon in Dallas, TX; must be a USPS record or something.
Its a bit interesting. I can see that the scroll appears larger externally and am assuming this transfers over to it being bigger internally. Yet they more or less kept it within the same basic profile. Stacking them directly centered on top of each other they are close to identical externally. When matched up on the same mounting surface the SX-E cover appears to be slightly taller, but not much. When the outlets are lined up to each other the SX-E cover outlet is about 0.25” taller (wider to the inlet side) or so. Yet the end of the inlet is about 0.37” shorter (just eyeballing it with a straight-edge across them). So it really doesn’t seem to take up any more space like I was expecting it to.
Supposedly a larger A/R, but no markings on any of them. It actually takes up less space without the integral BOV and solenoid valve, though the SX-E inlet is 3.5” dia. vs. 2.5” dia. for the standard EFR cover. So a larger CAI supply tube is required, but would have done that anyway with 4” and just reduced it at the inlet.
After looking at how the BOV is configured in the cover I’d conclude that that the openings in the outer scroll and inlet disrupt airflow relative to not having them in the SX-E cover, and certainly don’t contribute any benefit to keeping the the turbo spooled any better, as was suggested by someone in an earlier conversation. It just dumps the recirc air straight in from the side at about the center length position of the inlet perpendicular to flow and imo only serves as a convenience over an external BOV. Especially if it needs to be recirculated back to the inlet if a MAF is used rather than MAP.
fairly compact and simple in final form; EFR7163 converted to 7670 performance potential with SX-E cover, aluminum CHRA, and 1.25 A/R cast iron housing assembly came in just under 16 lbs total. A Garrett G30 divided T4 turbine housing weighs almost that much alone …
another potential contender, though at the supposed far end of the Renesis power limit (450+whp) as some contend it to be. I’m still thinking it needs to be pushed and explored more, but having not gone there yet have to admit that it’s not something that can be said with certainty.
One thing is for sure; the longer overall length of the EFR turbo coupled with the larger diameter of the SXE compressor cover make for a tighter fitment. It will fit though, but as with all Renesis turbo applications it's pretty much a design-to-fit job from start to end.
Originally Posted by TeamRX8
fairly compact and simple in final form; EFR7163 converted to 7670 performance potential with SX-E cover, aluminum CHRA, and 1.25 A/R cast iron housing assembly came in just under 16 lbs total. A Garrett G30 divided T4 turbine housing weighs almost that much alone …
Not so much, but perhaps some. Because as we discussed many times; as per my intention, by eliminating the OE type motor mount it opens up much more space for placing the turbo more forward. Particularly since the Renesis LIM loops way out with smooth long radius turns; optimum for NA, FI not so much.
But then this also started off as a 4-port engine exercise too and that LIM frees up more space as well as eliminating the APV piping and more importantly the APV actuator. The original 7163 turbine housing and compressor cover are smaller too; further assisting fitment, but likely too small on the turbine housing past 350 whp.
So while you’re a bit limited with going any bigger than a G30-660, I’m reasonable confident that the G30-770 can fit with my plan. But then we come to whether there really is a 450 whp limit and if that’s never exceeded then it’s a bit of a moot point wrt fitting a larger turbo down in the low mount position.
As you noted back at the time that comment is made; this is the reality of trying to fit a low-mount turbo on an RX8 Renesis. Because the other thing is the reply you copied had my manifold hand sketch and the other guy who did the EFR7163/Renesis build more or less did a variation of it on his 6-port. I also feel like AI is a bit under-appreciated on here. I wouldn’t build a Renesis turbo without it.
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it’s not actually what I meant; if you have space it won’t hurt, but compare it to an REW LIM. That’s why it’s so much easier to get a larger turbo fitted in the RX8 chassis with the REW. An EFR9180 to be exact per the pics below. The exhaust manifold mounting surface position is the same for both engines, but it’s not easy to recognize how much space there actually is until the Renesis LIM is not in the way hogging it all up.
Well that and the fact that the factory motor mount is eliminated with the REW engine mounting brace. It’s a bit more work to accomplish it with the Renesis, but not really much more than Brettus is already doing.
it’s not actually what I meant; if you have space it won’t hurt, but compare it to an REW LIM. That’s why it’s so much easier to get a larger turbo fitted in the RX8 chassis with the REW. ... but it’s not easy to recognize how much space there actually is until the Renesis LIM is not in the way hogging it all up.
Well that and the fact that the factory motor mount is eliminated with the REW engine mounting brace. It’s a bit more work to accomplish it with the Renesis, but not really much more than Brettus is already doing. .
Wrt flow the smooth radius of the LIM IS advantageous, but agreed wrt precious space... it is not.
Additionally, it is evidently well understood that the passenger motor mount is an obstacle, both Scott (RX8P) and Brett provide redesigned mounts to support their manifold designs.
They address it to some degree, but I neither have any problem with either kit or their methods, nor are my words intended that way. Hopefully my explanations will aid others who seek to do their own thing with a better understanding of the situation.
My advice to those people is always this; look at what has been done already and then try to envision how it can be done better. It applies even to them making an assessment of my own personal works and ideas. Because anyone with half a brain should be doing just that, right?
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08-22-2021, 04:23 PM
